INTEGRATING N-ENRICHED COMPOST WITH BIOLOGICALLY ACTIVE SUBSTANCES FOR IMPROVING GROWTH AND YIELD OF CEREALS

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1 Pk. J. Bot., 40(1): , INTEGRATING N-ENRICHED COMPOST WITH BIOLOGICALLY ACTIVE SUBSTANCES FOR IMPROVING GROWTH AND YIELD OF CEREALS R. AHMAD 1, M. ARSHAD 2, Z.A. ZAHIR 2*, M. NAVEED 2, M. KHALID 2 AND H.N. ASGHAR 2 1 Lnd Resources Reserch Progrm, Ntionl Agriculturl Reserch Centre, Islmd-54400, Pkistn 2 Institute of Soil & Environmentl Sciences, University of Agriculture Fisld-38040, Pkistn Astrct Vlue ddition of the composted orgnic wste mteril through iologiclly ctive sustnces (BAS) is novel pproch to convert composted mteril into useful soil mendment. In the present study, compost ws prepred from wste fruit nd vegetles nd enriched with 25% of full dose of N fertilizer for mize nd whet, respectively. Biologiclly ctive sustnces (BAS); indole 3-cetic cid (IAA), gierellic cid (GA 3 ) nd kinetin, ech ws 1.0 mg kg -1 compost to seprte tches of nitrogen enriched compost (NEC). Effectiveness of IAA, GA 3 nd kinetindded NEC ws compred in field in the presence of 50% recommended dose of N fertilizer for mize nd whet, respectively. Compost ws 300 kg h -1 to oth crops nd recommended P nd K fertilizers of respective crop were pplied s sl dose to ll plots. Recommended dose of N fertilizer for respective crop ws used for comprison. Results indicted tht NEC with or without IAA/GA 3 supplemented with hlf dose of N fertilizer ws s effective s full dose of N fertilizer in improving growth nd yield of mize s well s whet, sving ~ 25% N fertilizer. However, kinetin-dded compost ws etter thn IAA/GA 3 -dded compost when compred with recommended dose of N fertilizer. It significntly improved yield nd N uptkes of mize (6.2 nd 6.7%, respectively) nd whet (5.9 nd 6.1%, respectively) over full dose of N fertilizer. The technology ers its promise not only to improve crop yield on sustinle sis ut lso reduce huge piles of orgnic wstes cusing environmentl pollution. Introduction In griculture system, recycling of orgnic wste mterils is known to improve soil helth nd vilility of plnt nutrients y mending soil physico-chemicl nd iologicl properties (Ahmd et l., 2008). Diversified orgnic wstes like frm wstes, city wste (sewge-sludge), poultry litter nd industril wstes re eing ccumulted in huge mounts. Most of these orgnic wstes re either urnt or remin unutilized, especilly in developing countries. These prctices re not only posing serious thret to the environment, ut lso cusing loss of useful plnt nutrient sources which cn e used for crop production. Composting is n old technology of recycling orgnic wste mteril during which orgnic residues re io-chemiclly decomposed into stilized humified mteril under controlled conditions of temperture, moisture nd ertion (Ahmd et l., 2007). Interest is renewed in composting for sustining environment nd griculture side y side. The finished compost product hs desirle chrcteristics regrding odor, weed seed nd pthogens. It is most suitle nd economicl wste mngement strtegy thn others s hndling, storge nd frm ppliction of the composted product is environmentlly sfe (Ahmd et l., 2007). * Corresponding uthor: E-mil: zzhir@yhoo.com Phone: , Fx:

2 284 R. AHMAD ET AL., The composted or un-composted orgnic wste mteril is pplied in t h -1 in griculturl systems. Adequte storge nd trnsporttion fcility s well s extensive lor is required for their ppliction. This cn e overcome to some extent through improving qulity s well s nutrient sttus of compost so tht it my e pplied t sustntilly reduced rtes (kg h -1 ) thn trditionl ppliction rtes (t h -1 ). Enrichment of compost with nitrogen fertilizer (Ure) nd its lending with iologiclly ctive sustnces (BAS) is novel pproch to convert composted mteril into useful soil mendment (Zhir et l., 2007, ). Biologiclly ctive sustnces or PGRs re orgnic compounds, which hve shown frreching impcts on plnt growth even t low concentrtion. Auxin, plnt growth regultor, in pproprite concentrtion, my regulte cell elongtion, induction of cmium cell division, formtion of dventtitious roots, xillry shoot formtion, tropisms, cllus initition nd growth nd induction of emryogenesis (Vndehoff & Dute, 1981). Similrly, gierellins (GAs); lso plnt growth regultor, promote seed germintion, stem elongtion, flowering nd cone formtion. It lso fcilittes cell elongtion of different orgns nd tissues throughout plnt growth nd development nd retrd lef nd fruit senescence (Krssen et l., 1989). Kinetin, cytokinin, when dded in pproprite concentrtions my regulte cell division nd differentition. They re lso ssocited with senescence of plnt orgn, picl dominnce nd stomtl opening (Kr, 1997). These phytohormones re synthesized in plnt odies, however, their exogenous ppliction hs lso een reported to leve promising effects (Srwr & Frnkenerger, 1994). Plnts hve the ility to store the excessive mounts of exogenously pplied plnt hormones in the form of reversile conjugtes which relese ctive hormones when nd where plnt needs them during the growth period (Dvies, 1987). Although composting is n old technique, ut improving its nutritionl nd qulity sttus y lending it with inorgnic N (ure) nd BAS i.e. IAA, GA 3 nd kinetin is novel pproch. Accordingly, this study imed to improve growth nd yield of mize nd whet y integrting BAS-treted NEC nd chemicl fertilizers. Mterils nd Methods Preprtion of enriched compost: Compost ws prepred y using loclly fricted composting unit consisting of drier, crusher/ grinder nd processor. Wste fruit nd vegetles were collected from vrious loctions (fruit nd juice shops, fruit nd vegetle mrkets, etc.) of the city. Collected orgnic wste mteril ws ir-dried for 24 hours to remove the excess moisture nd unwnted sustnces if ny (plstic gs, glss mteril nd stones, etc.) were removed from the orgnic wste. The orgnic mteril ws then oven-dried t 55 o C for 24 hours nd ground to 2 mm y electricl grinder. Ground mteril ws put in the composter (processing unit) to convert rw orgnic wste mterils into compost. A moisture level of 40% (v/w) of the mteril ws mintined during composting. Composting ws done for 5 dys under controlled temperture nd ertion (shking t 50 rpm). Composted mteril (300 kg) ws enriched/lended with 25% of recommended (175 kg h -1 for mize nd 120 kg h -1 for whet) N fertilizer in the form of ure. Thus, 300 kg tch of compost received 44 kg N for mize nd 30 kg N for whet crop. To formulte vlue-dded orgnic fertilizer, ech of IAA, GA 3 nd kinetin were 1.0 mg kg -1 compost to respective tches of N-enriched compost.

3 INTEGRATING N-ENRICHED COMPOST WITH BIOLOGICALLY ACTIVE SUBSTANCES 285 Both rw (non-composted) nd composted orgnic wste mterils were nlyzed for cron content (Nelson & Sommers, 1996), nd mcro- nd micro-nutrients (Ryn et l., 2001). The C/N, C/P nd C/K rtios were lso clculted (Tle 1). Field trils: Field experiments were conducted t Agronomy Reserch Are, Ayu Agriculture Reserch Institute, Fisld during , to ssess the effect of enriched compost nd chemicl fertilizers on the growth nd yield of whet nd mize crops. Soil ws collected, ir dried, sieved nd nlyzed for physico-chemicl chrcteristics (Tle 2) efore sowing the crop. Hyrid Corn-786 (mize) nd Inqul- 91 (whet) vrieties were 30 nd 100 kg h -1, respectively. Row to row distnce of 75 cm in mize nd 25 cm in whet were mintined with plot size of 10 m 2. The experiments were lid out in rndomized complete lock design with four replictions s: T1: Recommended chemicl N fertilizer (175 nd 120 kg h -1 for respective crops) T2: N-enriched compost + 50% N fertilizer for respective crops T3: IAA-treted N-enriched compost + 50% N fertilizer for respective crops T4: GA 3 -treted N-enriched compost + 50% N fertilizer for respective crops T5: Kinetin-treted N-enriched compost + 50% N fertilizer for respective crops The NPK fertilizers were in mize nd kg h -1 in whet s ure, SSP nd SOP, respectively. Full dose of N (175 nd 120 kg h -1 for mize nd whet, respectively) ws kept for comprison. The whole mounts of P nd K fertilizers were pplied t the time of sowing s sl dose in ll plots, while N ws pplied ccording to the tretments (Figs. 1-6) in two split pplictions i.e., fter germintion nd efore/t tssling/tillering. Biologiclly ctive sustnces (BAS)- treted NEC ws pplied in the presence of 50% full dose of N fertilizer for mize s well s for whet to compre with the full dose of N fertilizer. Compost-sed orgnic fertilizer ws 300 kg h -1 long the plnt rows with drill t the time of first dose of N fertilizer ppliction nd it ws followed y irrigtion immeditely. Cnl wter (electricl conductivity = 0.03 ds m -1, sodium dsorption rtio = 0.26 (mmol L -1 ) 1/2, residul sodium cronte = 0) meeting the irrigtion qulity criteri for crops (Ayers & Westcot, 1985) ws used for irrigtion in oth crops. The plnts were hrvested t mturity nd dt regrding growth nd yield prmeters were recorded. Grin nd shoot smples of plnts were nlyzed for N content (Ryn et l., 2001) nd their totl contents were determined. The dt were nlyzed y using completely rndomized design (Steel et l., 1997). Mens were compred y Duncn's Multiple Rnge Test (Duncn, 1955). Results Two field trils on mize nd whet were conducted to test the effectiveness of BAStreted NEC in the presence of N fertilizer. Mize tril: Dt regrding the effect of NEC treted with different BAS in the presence of N fertilizer on growth, yield nd N uptke of mize is presented in Figs Mximum plnt height ws oserved where kinetin-lended NEC ws supplemented with 88 kg h -1 N tht differed significntly from full dose of N fertilizer (Fig. 1). It ws followed y IAA-lended NEC. Appliction of NEC with or without GA 3 in comintion with 88 kg h -1 N produced sttisticlly similr plnt height s ws produced y full dose of N fertilizer.

4 286 R. AHMAD ET AL.,

5 INTEGRATING N-ENRICHED COMPOST WITH BIOLOGICALLY ACTIVE SUBSTANCES 287 Tle 2. Physico-chemicl chrcteristics of soil used for study. Prmeters Mize Whet Texture Sndy cly lom Sndy cly lom ph Orgnic mtter (%) Totl nitrogen (%) Aville phosphorus (mg kg -1 ) Extrctle potssium (mg kg -1 ) Significntly higher fresh iomss (6%) ws produced y kinetin-treted NEC plus 88 kg h -1 N compred to full dose of N fertilizer (Fig. 1). Enriched compost treted with IAA or GA 3 differed non-significntly with ech other s well s with kinetin-treted NEC regrding fresh iomss production. There ws lso non-significnt difference etween NEC plus 88 kg h -1 N nd full dose of N fertilizer. Like fresh iomss, mximum co yield ws recorded with the ppliction of kinetin-lended NEC plus 88 kg h -1 N nd it ws 8.2% greter thn full dose of N fertilizer (Fig. 2). It ws followed y NEC treted either with IAA or GA 3. Similr results were recorded y full dose of N fertilizer nd y the tretment where NEC ws supplemented with hlf dose of N fertilizer without ny BAS. Appliction of kinetin-treted NEC plus 88 kg h -1 N resulted in significntly higher grin yield (6.2%) over full dose of N fertilizer (Fig. 2). Grin yield in response to the ppliction of NEC treted either with IAA or GA 3 ws sttisticlly similr ut differed significntly with full dose of N fertilizer nd N-enriched compost in the presence of hlf dose of N fertilizer. In cse of 1000-grin weight, effect of BAS-treted /untreted NEC in the presence of 88 kg h -1 N ws sttisticlly t pr with ech other s well s with full dose of N fertilizer (Fig. 3). The mximum 1000-grin weight (312 g), however, ws otined where kinetin-treted NEC ws pplied in the presence of 88 kg h -1 N fertilizer. Similrly, significntly higher (6.7%) N uptke ws recorded y the ppliction of kinetin-treted NEC plus 88 kg h -1 N compred to full dose of N fertilizer nd it ws followed y GA 3 -treted NEC (Fig. 3). Uptke of N y NEC long with hlf dose of N fertilizer differed non significntly with full dose of N. However, ddition of IAA showed non-significnt effect on N uptke over untreted NEC. Whet tril: Dt regrding the effect of NEC treted with different BAS in the presence of N fertilizer on growth, yield nd N uptke of whet is presented in Figs Significntly higher plnt height (4.4%) ws oserved y the ppliction of kinetin treted NEC plus 60 kg h -1 N over full dose of N fertilizer (Fig. 4). It ws followed y NEC treted with IAA. No significnt improvement in plnt height ws recorded y lending GA 3 in NEC supplemented with 60 kg h -1 N compred to unlended compost. Both the tretments lso differed non-significntly with full dose of N fertilizer. Mximum numer of tillers m -2 (466) were recorded due to the ppliction of kinetin-treted NEC comined with 60 kg h -1 N i.e., 8.3% more thn full dose of N fertilizer (Fig. 4). Next ws IAA-treted NEC. Enriched compost in the presence of 60 kg h -1 N with or without GA 3 differed non-significntly with full dose of N fertilizer regrding numer of tillers m -2.

6 288 R. AHMAD ET AL., Plnt height (cm) Plnt height Fresh iomss c c c Fresh iomss (t h -1 ) 200 Tretment 30 Fig. 1. Effect of compost enriched with different BAS nd supplemented with chemicl fertilizers on plnt height nd fresh iomss of mize. T1, Ure fertilizer 175 kg h -1 N; T2, NEC plus 88 kg h -1 N; T3, IAA-treted NEC plus 88 kg h -1 N; T4, GA 3 - treted NEC plus 88 kg h -1 N; T5, Kinetin-treted NEC plus 88 kg h -1 N. 18 Co yield Grin yield 7 Co yield (t h -1 ) c c Grin yield (t h -1 ) 14 c c Tretment 5 Fig. 2. Effect of compost enriched with different BAS nd supplemented with chemicl fertilizers on co nd grin yield of mize. T1, Ure fertilizer 175 kg h -1 N; T2, NEC plus 88 kg h -1 N; T3, IAA-treted NEC plus 88 kg h -1 N; T4, GA 3 - treted NEC plus 88 kg h -1 N; T5, Kinetin-treted NEC plus 88 kg h -1 N.

7 INTEGRATING N-ENRICHED COMPOST WITH BIOLOGICALLY ACTIVE SUBSTANCES grin weight Totl N uptke grin weight (g) NS Totl N uptke (kg h -1 ) 300 Tretment 102 NS: Non-significnt Fig. 3. Effect of compost enriched with different BAS nd supplemented with chemicl fertilizers on 1000-grin weight nd totl N uptke of mize. T1, Ure fertilizer 175 kg h -1 N; T2, NEC plus 88 kg h -1 N; T3, IAA-treted NEC plus 88 kg h -1 N; T4, GA 3 - treted NEC plus 88 kg h -1 N; T5, Kinetin-treted NEC plus 88 kg h -1 N Plnt height No. of tillers c Plnt height (cm) c c No. of tillers m Tretment Fig. 4. Effect of compost enriched with different BAS nd supplemented with chemicl fertilizers on plnt height nd numer of tillers m -1 of whet. T1, Ure fertilizer 120 kg h -1 N; T2, NEC plus 60 kg h -1 N; T3, IAA-treted NEC plus 60 kg h -1 N; T4, GA 3 - treted NEC plus 60 kg h -1 N; T5, Kinetin-treted NEC plus 60 kg h -1 N.

8 290 R. AHMAD ET AL., Greter increse (6% over full dose of N) in spike length ws produced y NEC treted either with kinetin or IAA long with 60 kg h -1 N tht differed significntly with rest of the tretments (Fig. 5). Spike lengths otined in response to NEC nd full dose of N were like nd sttisticlly similr to GA 3 treted NEC. Likewise, significntly higher (y 5.9%) grin yield resulted in response to kinetintreted NEC supplemented with 60 kg h -1 N thn full dose of N fertilizer (Fig. 5). The grin yield resulted with the ppliction of enriched compost treted either with IAA or GA 3 differed non significntly with ech other nd with full dose of N fertilizer. The grin yield produced y the integrtion of NEC nd 60 kg h -1 N ws sttisticlly t pr with the yield produced y full dose of N fertilizer. Effect of compost treted with different BAS on 1000-grin weight reveled tht significntly higher (43.5 g) grin weight ws recorded in response to kinetin-treted NEC plus 60 kg h -1 N followed y enriched compost lended with IAA in the presence of sme quntity of N (Fig. 6). Non significnt ( g) thousnd grin weight ws recorded y rest of the tretments. Like 1000-grin weight, kinetin-treted NEC in conjunction with 60 kg h -1 N resulted in significntly higher N uptke (6.1%) over full dose of N fertilizer (Fig. 6). Sttisticlly similr ( kg h -1 ) N uptkes were oserved y rest of the tretments. Discussion This study ws conducted to sses the effect of NEC treted with different BAS in the presence of chemicl N fertilizer on growth nd yield of mize nd whet. Results reveled tht compost enriched/mixed with 25% of full dose of mize nd whet plus 50% of full dose of N fertilizer of respective crops, 300 kg h -1 ws comprle to full dose of N fertilizer in improving growth nd yield of mize nd whet. Addition of the IAA or GA 3 to NEC showed no significnt improvement in the growth nd yield of oth crop in the presence of their hlf N fertilizer dose when compred with their full dose of N fertilizer. However, enrichment of the compost with kinetin showed more promising results in the presence of hlf N fertilizer dose nd significntly incresed growth nd yield of oth crops under field conditions compred with full dose of N fertilizer. This work indictes tht BAS cn hve n ecologicl effect in modifying plnt growth nd development. The mechnism of ction of BAS on plnt growth my e ttriuted to direct uptke of these compounds y plnt roots, chnge in the rhizosphere microflor discourging root pthogens or y microil conversion into metolites resulting in eneficil rhizosphere for plnt growth s reported y other workers (Srwr & Frnkenerger, 1994; Khn et l., 2002; Zhir et l., 2001, 2007). Increses in growth nd yield of mize nd whet in our study could lso e ttriuted to enhnced N use efficiency nd physiologicl response of crops to dded BAS in the presence of orgnic fertilizer (Tle 1). This premise is supported y the fct tht the totl N uptke in mize nd whet (Figs. 3 & 6) were incresed significntly in response to comined ppliction of enriched compost nd N fertilizer. Previous studies hve lso shown tht the composted orgnic mterils enhnce N fertilizer use efficiency y relesing it slowly nd thus reducing its losses (Pul & Clrk, 1996; Muneshwr et l., 2001; Nevens & Reheul, 2003). In our erlier reports BAS-dded NEC ws lso found more effective thn untreted NEC for whet, mize nd rdish (Asghr et l., 2006; Zhir et l., 2007; Ahmd et l., 2007). Overll, there ws ~ 25% sving of N- economy with the ppliction of 300 kg h -1 orgnic fertilizer/enriched compost. Reserchers hve reported ~20% N sving due to the ppliction of compost (Bjpi et l., 2002; Poorn et l., 2002); however, they pplied compost in tons h -1.

9 INTEGRATING N-ENRICHED COMPOST WITH BIOLOGICALLY ACTIVE SUBSTANCES Spike length Grin yield Spike length (cm) c c Grin yield (t h -1 ) Tretment Fig. 5. Effect of compost enriched with different BAS nd supplemented with chemicl fertilizers on spike length nd grin yield of whet. T1, Ure fertilizer 120 kg h -1 N; T2, NEC plus 60 kg h -1 N; T3, IAA-treted NEC plus 60 kg h -1 N; T4, GA 3 - treted NEC plus 60 kg h -1 N; T5, Kinetin-treted NEC plus 60 kg h -1 N grin weight Totl N uptke grin weight (g) Totl N uptke (kg h -1 ) Tretment 79 Fig. 6. Effect of compost enriched with different BAS nd supplemented with chemicl fertilizers on 1000-grin weight nd totl N uptke of whet. T1, Ure fertilizer 120 kg h -1 N; T2, NEC plus 60 kg h -1 N; T3, IAA-treted NEC plus 60 kg h -1 N; T4, GA 3 - treted NEC plus 60 kg h -1 N; T5, Kinetin-treted NEC plus 60 kg h -1 N.

10 292 R. AHMAD ET AL., The novelty of our pproch is tht the enriched compost ws pplied 300 kg h -1. Previously, reserchers investigted the effect of compost/rw orgnic mteril y pplying it in severl tons h -1 (Nevens & Reheul, 2003; Wolkowski, 2003). The economic nlysis of the BAS-treted enriched compost indicted tht insted of IAA or GA 3, the use of kinetin is cost effective. The rw mteril is ville free of cost nd ppliction of just 300 kg h -1 is quite fesile for the frmers, nd will not crete the prolem of demnd-supply imlnces. Moreover, use of orgnic fertilizer could reduce dependence on chemicl fertilizers to some extent. The improvement in soil helth nd reduction in piling of orgnic wstes could e extr enefit. Further reserch is needed to unlock severl horizons like physiochemicl trnsformtion of BAS in the soil, screening efficient nd inexpensive precursors of BAS nd gronomic prctices which could enhnce the stility nd iovilility of BAS in plnt root zone. Judicious use of iologiclly ctive sustnces (BAS) could e very helpful for the prosperity of griculture industry. References Ahmd, R., G. Jilni, M. Arshd, Z.A. Zhir nd A. Khlid Bio-conversion of orgnic wstes for their recycling in griculture: n overview of perspectives nd prospects. Ann. Microiol., 57(4): Ahmd, R., S.M. Shehzd, A. Khlid, M. Arshd nd M.H. Mhmood Growth nd yield response of whet (Triticum estivum L.) nd mize (Ze mys L.) to nitrogen nd L- Tryptophn enriched compost. Pk. J. Bot., 39(2): Ahmd, R., M. Arshd, A. Khlid nd Z.A. Zhir Effectiveness of orgnic-/io-fertilizer supplemented with chemicl fertilizers for improving soil wter retention, ggregte stility, growth nd nutrient uptke of mize (Ze mys L.). J. Sustin. Agri., 31(4): Asghr, H.N., M. Ishq, Z.A. Zhir, M. Khlid nd M. Arshd Response of rdish to integrted use of nitrogen fertilizer nd recycled orgnic wste. Pk. J. Bot., 38(3): Ayers, R.S. nd D.W. Westcot Wter Qulity for Agriculture. FAO Irrigtion nd Dringe ppers 29 (Rev. 1). FAO, Rome. Bjpi, R.K., S.K. Updhyy, B.S. Joshi nd R.S. Tripthi Productivity nd economics of rice (Oryz stiv L.)-whet (Triticum estivum) cropping system under integrted nutrient supply systems. Ind. J. Agron., 47: Dvies, J.P Plnt hormones nd their role in plnt growth nd development. Mrtinus Nijhoff, Dordrecht. Duncn, D.B Multiple rnge nd multiple F-test. Biometrics, 11: Kr, K Comprison of reversl of scisic cid induced inhiition of seed germintion nd seedling growth of some Grminee nd Lilicee memers y Kinetin nd Gierellic cid. Turkish J. Bot., 63: Krssen, C.M., S. Zgorski, J. Kepczynski nd S.P.C. Groot Key role for endogenous gierellins in the control of seed germintion. Ann. Bot., 63: Khn, N.A., R. Mir, M. Khn nd Smiullh Effects of gierellic cid spry on nitrogen yield efficiency of mustrd grown with different nitrogen levels. Plnt Growth Reg., 38: Muneshwr, S., A.K. Tripthi, K.S. Reddy nd K.N. Singh Soil phosphorus dynmics in Vertisol s ffected y cttle mnure nd nitrogen fertiliztion in soyen-whet system. J. Plnt Nutr. Soil Sci., 164(6): Nelson, D.W. nd L.E. Sommers Totl cron, orgnic cron nd orgnic mtter. In: Methods of Soil Anlysis: Prt 3-Chemicl Methods. (Ed.): J.M. Bighm. Soil Science Society of Americ, Mdison, USA.

11 INTEGRATING N-ENRICHED COMPOST WITH BIOLOGICALLY ACTIVE SUBSTANCES 293 Nevens, F. nd D. Reheul The ppliction of vegetle, fruit nd grden wste (VFG) compost in ddition to cttle slurry in silge mize monoculture: nitrogen vilility nd use. Europ. J. Agron., 19: Pul, E.A. nd F.E. Clrk Soil microiology nd iochemistry. Acdemics Press, Sn Diego, CA. Poorn, C., P.K. Singh, M. Govrdhn nd P. Chnd Integrted mngement in rinfed cstor (Ricinus communis). Ind. Prog. Agri., 2: Ryn, J., G. Estefn nd A. Rshid Soil nd Plnt Anlysis: Lortory Mnul. Int. Centre Agri. Res. in Dry Ares (ICARDA) Aleppo. 172 pp. Srwr, M. nd W.T. Frnkenerger. Jr Influence of L-tryptophn nd uxins pplied to rhizosphere on the vegettive growth of Ze mys L. Plnt Soil, 160: Steel, R.G.D., J.H. Torrie nd D.A. Dicky Principles nd Procedures of Sttistics- A Biometricl Approch (3rd Ed.) McGrw-Hill Book Interntionl Co., Singpore. p Vnderhoff, L.N. nd R.R. Dute Auxin-regulted wll loosening nd sustined growth in elongtion. Plnt Physiol., 67: Wlkowski, R.P Nitrogen mngement considertions for lnd spreding municipl solid wste compost. J. Environ. Qul., 32: Zhir, Z.A., H.N. Asghr nd M. Arshd Cytokinin nd its precursors for improving growth nd yield of rice. Soil Biol. Biochem., 33: Zhir, Z.A., M. Iql, M. Arshd, M. Nveed nd M. Khlid Effectiveness of IAA, GA 3 nd kinetin lended with recycled orgnic wste for improving growth nd yield of whet (Triticum estivum L.). Pk. J. Bot., 39(3): Zhir, Z.A., M. Nveed, M.I. Zfr, H.S. Rehmn, M. Arshd nd M. Khlid Evlution of composted orgnic wste enriched with nitrogen nd L-tryptophn for improving growth nd yield of whet (Triticum estivum L.) Pk. J. Bot., 39(5): (Received for puliction 10 Decemer 2007)